The main antagonist, Naraku (literally means "underworld", or "hell") is responsible for nearly every character’s suffering throughout the series. He is a han'you that originated from a bandit named Onigumo ("Demon Spider"). Naraku's main goal is to collect all of the shards of the Shikon no Tama in order to become a full Youkai. His platonic love for Kikyo is what drove him to kill Kikyo and seal Inuyasha on the tree and the basic reason he became a demon.

When people talk about a knife's edge between pleasure and pain, they are usually talking about their own pain. But these people like to get their kicks from the pain of others. These people will make you scream while they grin from ear to ear.